DosSemSet

This call unconditionally sets a semaphore; that is, it sets the semaphore whether or not it is already set.

DosSemSet

(SemHandle)

SemHandle (HSEM) - input

Reference to the semaphore.

For a system semaphore, this reference is the handle returned by a DosCreateSem or DosOpenSem request that granted the requesting thread access to the semaphore.

For a RAM semaphore, this reference is the address of a doubleword of storage, allocated and initialized to zero by the application. This sets the semaphore as unowned. Other than initializing the doubleword to zero, an application must not modify a RAM semaphore directly; instead it manipulates the semaphore with semaphore function calls.

rc (USHORT) - return
Return code descriptions are:
• NO_ERROR 100
  ERROR_TOO_MANY_SEMAPHORES
  103
  ERROR_TOO_MANY_SEM_REQUESTS
  Remarks

  DosSemSet usually is not required in a resource control environment using DosSemRequest and DosSemClear. It typically is used in a signaling environment implemented with DosSemWait, DosMuxSemWait, and DosSemClear. These function calls are used to block one or more threads on a set semaphore and awaken them when an event occurs.

  DosSemSet cannot be issued against a system semaphore that is owned by another thread, unless the NoExclusive option was set in the original DosCreateSem request.

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